113 lines
2.8 KiB
ReStructuredText
113 lines
2.8 KiB
ReStructuredText
.. _intro_tut:
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Introductory Tutorials
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======================
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These introductory tutorials will give you an overview of how to run
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Conquest, the files and parameter settings required, and what output
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to expect.
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.. _intro_one:
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Bulk silicon: input, output and SCF
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-----------------------------------
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We start with a very basic introduction to the input
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required for CONQUEST, the output generated, and the self-consistency
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(SCF) procedure; it uses the same system as the first of the examples
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in the manual, but provides more detail. The files are found in
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``docs/tutorials/Introductory_1``.
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CONQUEST requires the following files to run:
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* The input file: ``Conquest_input``
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* A coordinates file (name set in ``Conquest_input``; no default)
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* Ion files (suffix ``.ion``), which provide the pseudopotentials and
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pseudo-atomic orbitals (PAOs)
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The input file requires the user to provide a certain amount of
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information. The minimal file that is provided for this tutorial
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gives most of these:
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::
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# Input/Output
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IO.Title Bulk Si 8 atoms static
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IO.Coordinates ionpos.dat
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# General Parameters
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General.NumberOfSpecies 1
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%block ChemicalSpeciesLabel
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1 28.0850 Si_SZ
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%endblock
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# Moving Atoms
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AtomMove.TypeOfRun static
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# Finding the density matrix
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DM.SolutionMethod diagon
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# k-points
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Diag.GammaCentred T
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Diag.MPMesh T
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Diag.MPMeshX 2
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Diag.MPMeshY 2
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Diag.MPMeshZ 2
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The key entries are:
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* the coordinate file (``IO.Coordinates``);
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* the number of species (``General.NumberOfSpecies``);
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* the specification for the species (the block
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``ChemicalSpeciesLabel`` gives the atomic mass and the ion file name
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for all species);
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* the type of run (``AtomMove.TypeOfRun`` which defaults to ``static``)
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The Brillouin zone sampling must be investigated carefully, as for
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all periodic electronic structure calculations. The Monkhorst-Pack
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mesh (``Diag.MPMesh``) offers a convenient way to do this systematically.
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The job title is purely for reference. Further parameters are
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discussed in the next tutorial
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* The coordinate file ``IO.Coordinates``
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* The number of species ``General.NumberOfSpecies``
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* The ion files for the species
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* The basic input file
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* The output
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* Changing the output level and destination
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* Controlling the SCF (tolerance and iterations, options)
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.. _intro_two:
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Bulk silicon: parameters to converge
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------------------------------------
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* The files that are needed
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* Coordinates
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* Ion files
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* Input file: ``Conquest_input``
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* Integration grid
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* Brillouin zone sampling
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* Possibly basis set size
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.. _intro_three:
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Bulk silicon: analysis
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----------------------
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* The files that are needed
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* Coordinates
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* Ion files
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* Input file: ``Conquest_input``
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* Total DOS
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* Atom-projected DOS
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* Band structure output
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* Charge density and bands
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* Atomic charges
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